Sliders for slide fasteners



March 13, 1956 y H. ERDMANN 2,737,699

SLIDER FOR SLIDE FASTENERS Filed Feb. 15, 1952 2 Sheets-Sheet l FIG. 2-

"- FIG. 3

Inventor I30 /3b HANS ERDMANN,

I 25 266 By J &

At forney March 13, 1956 H. ERDMANN 2,737,699

SLIDERS FOR SLIDE FASTENERS Filed Feb. 15, 1952 2 Sheets-Sheet 2 Inventor HANS ERDMANN,

Attorney States Patent 2,737,699 Patented Mar. 13, 1956 SLIDERS FOR SLIDE FASTENERS Hans Erdmann, Maplewood, N. J., assignor to Waldes Kohinoor, Inc., Long Island City, N. Y., a corporation of New York 1 Application February 15, 1952, Serial No. 271,688

7 Claims. (Cl. 24205.14)

This invention relates to improvements in sliders for slide fasteners, and more particularly to an improved automatic locking slider of the general type wherein a locking pin carried by a spring functioning as a leaf spring normally assumes a locking position in which it arrests movement of the slider at any point of its travel along the fastener, but may be raised out of its locking position by movement of the pivot pin or trunnions of the slider pull tab against a cam surface or surfaces provided on the spring.

A conventional slider for interengaging and separating the opposite fastener elements of a slide fastener or zipper comprises two parallel wings connected by a neck por- 7 tion which is preferably indented so as to strengthen this portion against the high bending stresses to which it is exposed. Usually, the inner surface of the indentation forms the so-called divider which separates the interengaged elements when the slider is moved in proper direction to open the fastener, with movement of the slider in the opposite direction causing interlocking of the elements as they move relatively throughtthe slider channel. Such a slider is actuated by a finger piece or pull tab which is pivotally and slidably connected to the upper wing by a so-called bail which may be struck up from the material of the upper wing.

To render such a slider self-locking, it is known to mount a spring, usually a leaf spring, in the space between the upper wing and bail, the spring carrying a locking pin which normally projects into the slider channel, and more particularly into the space between two adjacent fastener elements of the same row thereof, whereby the locking pin in its normal position arrests movement of the slider at any point of its travel along the slide fastener. The aforesaid spring is provided with a cam surface (or surfaces) which, when engaged by the pull tab pintle or trunnions as the pull tab is raised and pull exerted thereon in fastener opening direction, effects lifting of the locking pin out of the path of the fastener elements contained within the slider channel so that the slider can be freely actuated as desired. On release of the pull tab, the spring and consequently the locking pin automatically return to their normal or locking position.

.Dlfiiculties have been encountered in designing, assembling and securing such a leaf spring which, for convenience, is hereinafter referred to as a locking spring, so that it works to greatest advantage. In an effort to solve these difliculties, I proposed in my prior application Serial No, 136,689, filed January 4, 1950, now Patent No. 2,622,296, dated December 23, 1952, to em ploy a locking spring of substantial U-shape which is positioned by inserting the spring through an'opening in the upper wing immediately below the hail from the under face of said wing and before the slider blank is folded, i. e. its wings brought to their final parallel rela* tionship. Securement of such a locking spring according to my prior application was effected by providing extended portions on the lower arm thereof which seat in recesses provided in the under face of the upper wing and by peening the material of the wing adjacent the recesses over such extended portions, thereby to more or less rigidly afiix the free end of the lower arm of the spring to the upper slider wing.

While functioning effectively for the purpose intended, further experience with a locking spring mounted and secured as aforesaid revealed that, in addition to the separate peening operation required to secure the spring, only one arm thereof acts as a leaf spring, and since this one arm was required to have substantial stiffness for proper operation, the force required to lift the locking pinhout of the path of the elements was comparatively hig m It is a principal object of the present invention to improve the ease of operation and sensitivity of a locking spring of the general type disclosed in my prior application aforesaid by so mounting and securing the locking spring that both of its arms may function as leaf springs, thereby'to reduce the force required to be applied to the locking spring by the pull tab to raise the locking pin out of the path of the fastener elements.

It is a further object of the invention to provide an automatic locking slider employing a U-form locking spring of the general type disclosed in my prior application aforesaid, but characterized in that the free ends of both spring arms are loosely, i. e. non-fixedly, secured to the upper slider wing, whereby each spring arm may flex relatively to the other with respect to the slider upper wing as well, with the flexing movement of both spring arms contributing to the lifting stroke of the locking pin located near the bend or bight portion of the spring.

A more specific object of the invention is the provision of an improved slider locking spring and a novel and effective connection of the same to the upper wing of the slider, which permits of a limited bodily rotational movement of the locking spring in the direction of the lifting force applied to the locking pin by the pull tab trunnions.

Yet another detailed object of the invention is the provision of an automatic locking slider employing a U- form locking spring which is effectively connected to the upper wing of the slider by loosely securing the free ends of both arms thereof in recesses formed in the outer and under faces, respectively, of the upper wing, and in such manner that the bottom and/ or edges of the recesses form abutments against which the free end portions of the spring arms press and are thereby spread upon the pull tab being actuated to raise the locking pin out of the path of the fastener elements.

Another important feature of the invention resides in the simple assembly of a U-form locking spring with the slider body, which the invention makes possible, according to which the spring is merely clipped on to the upper wing of the slider while the slider blank is still unfolded yet is thereby effectively secured in place without any further securing operations, such as riveting, peening or the like, being required.

The above and other objects and features of advantage will be apparent from the following detailed description of an automatic locking slider according to the invention, taken with the accompanying drawings, in which:

Fig. 1 is a longitudinal section taken through an automatic locking slider of the invention, with the locking.

pin in its rest or normal locking position;

Fig. 2 is a view similar to Fig. 1 but illustrating the locking pin raised out of the path of the fastener elements contained within the slider channel;

Fig. 3 is a transverse section taken along line 3-3 of Fig. 1;

Fig. 4 is a plan view looking on to the under face of the upper wing of the slider, the lower wing being removed;

Fig. 5 is a top plan view of the slider illustrated in Fig. l; and

Fig. 6 is a longitudinal section taken through the slider blank before folding thereof, which illustratesthe mode of assembling the locking spring with respect to the upper wing portion of the slider blank prior to finalfolding of the blank.

Referring to the drawings, an automatic locking slider according to the invention is shown to comprise an upper wing 19 and a lower wing 11 having side edges bent to form flanges 12a, 12b and 13a, 13b, respectively, which define a Y-shaped slider channel and also serve to guide the fastener elements in their movement through the channel as the slider is actuated in either direction along the fastener. The slider wings and 11 are connected as usual by an indented neck portion 14- which also functions as a divider for. separating. the interengaged fastener elements when the slider is actuated in slider opening (downward) direction. Such a slider is actuated by means of a fingerpiece or pull tab 15 pivotally connected to the upper wing 10 as by trunnions 16, 17 (or a hinge pin) which project into an elongated eye of a bail 18, the elongation of the eye permitting limited sliding movement of the trunnions. Preferably, the bail. 18 is struck out from the material of the upper wing 10, thus leaving a generally rectangular opening 19 in said upper wing. Excessive lifting of the pull tab is prevented by inwardly directed ribs 24) depending from the side edges of the bail, the ribs also insuring that the trunnions 16, 17 slide in a straight line path along the upper wing.

According to the invention, and as best seen in Figs. 1, 2 and 6, the upper wing 10 is provided on its longitudinal center line with a recess 21 sunk into its outer face, the

recess extending from the upper or neck-end edge 19a of the wing opening 19 and terminating at its upper end in a recess portion 21a of somewhat greater depth than the recess 21 proper. A center-line recess 22 is also sunk into the under face of the upper wing, such recess similarly extending upwardly from the aforesaid upper or neck-end edge 19a of the wing opening 19. However, as seen in Fig. 4, the recess 22 has shorter length than the length of the outer face recess 21 so that it is in effect offset in longitudinal direction, i. e. toward the bottom (right) end of the slider from the upper recess, and its upper end is widened transversely as at 22a so that it is shaped in plan as a T. As will be later ,explained in detail, the recesses 21, 22, serve as seats for the ends of a locking spring generally designated 23, and,

additionally, the recess bottoms and edges are adapted to provide abutment surfaces against which the ends of the locking spring engage.

The locking spring 23 consists of a piece or strip of spring metal bent to modified U-form. One arm 24 of said locking spring, shown to be the lower arm, operates within the upper wing opening 19 and accordingly extends generally straightway and it is moreover provided near the bend portion which integrally connects it with the other or upper arm of the spring with a locking pin 25, which later, in the normal position of the spring (Fig. 1) depends into the space between two fastener elements of the same row thereof contained within the slider channel. To illustrate this locking action, it will be assumed that the fastener elements 26, 26a, 26b and 26c of the farther row thereof (as seen in Figs. 1 and 2) are contained within the channel, of which elements 26, 26a and 26b have been-disengaged from elements of the opposite (nearer) row by the action of the divider 14. However, element'26c is shown to be still connected to a lowermost opposite'fastener element designated 27, and locking pin is shown'in its normal-locking position in which it abuts against the upper side face of said element 27, thus preventing movement of the slider in downward or'rightwise direction, as viewed in Figs. 1 and 2.

Again referring particularly to Fig. 4, the free end portion of the spring arm 24, i. e. the end opposite the locking pin 25, is extended in transverse direction as at 28, so that this end has general T-shape corresponding to the T-shape of the recess 22. It is to be understood that the width of the spring arm 24 is slightly less .han the width of the recess 22, and that the dimensions of the transversely extended end portion 22 of the spring arm are slightly less than those of the recess portion 22:5.

The other'arrn of the spring 23, hereinafter designated arm 29, is arranged to overlie the pull tab trunnions .6, 17 and, like said trunnions, is contained and operates within the eye of the bail 18. Said spring arm 29 has a straight middle portion 290, which extends substantially parallel to the slider wings wand '11 in the normal position of the locking spring, and oppositely inclined portions 291), 290 which slope from the middle portion 29a at an angle of approximately 45, the portion 2131) being integrally connected to the lower spring arm 2K- and the portion 290 being integrally connected to the straight free end portion 290! of said arm which projects through an opening 18a in the bail and whose terminus is bent angularly to hook form, as indicated at 3%. It is to be understood that the width of the free end portion 29:! and of its hook and 30 is slightly less than the width of the outer face recess 21 of the upper wing.

Upon final assembly of the locking spring, the T-end 28 of the lower spring arm 24 loosely, i. e. non-fixedly, seats in the recess 22, 22a, and the flat end portion 2ft! of the upper spring arm 29 loosely seats in the recess 21, with its hook end 30 similarly loosely seating in the deeper recess portion 21a. Due to the fact that the aforesaid recesses provide edge surfaces against which all edges of the free end portions of the spring arms abut or may abut, and considering that the spacing between the free ends of the spring arms corresponds closely to the thickness of the wing portion 31 intermediate the recesses, all as generally shown in Figs. 1, 2 and 6, no additional means of securing the locking spring are required. Thus, it will be seen that this form of mounting and connection of locking spring not only makes unnecessary any riveting, peening and like fixed forms of connection previously employed, but also it achieves a perfectly secure attachment of the spring to upper Wing 10, since the spring is held against longitudinal, sidewise and up anch down movement due to the interlocking and interfitting arrangement of spring ends in upper wing recesses.

The operation of a locking slider as aforesaid will be readily understood from a comparison of Figs. 1 and 2. Referring to Fig. 1, the locking spring is shown in its normal rest or locking position, that is to say, with no pull on the pull tab 15, the trunnions 16, 17 thereof underlie the straight middle part 29a of the upper arm of the locking spring and hence exert no lifting force on either of the cam portions 29b, 29c thereof. In this position of the pull tab trunnions, locking pin 25, due to a certain pre-tension imparted the locking spring, projects into the slider channel and locks with one of the fastener elements contained therein, shown to be the fastener element 27, so that the slider is prevented from moving in downward (rightwise) direction. However, when the pull tab 15 is raised and pull exerted thereon, the pulltab trunnions 16, 17 engage the cam surface 2% of the upper spring arm 29, thus lifting the locking pin out of the path of element 27, or any other of the elements contained within the slider channel, whereby the slider may be actuated more or less freely in downward or fastener opening .direction.

Consequent to the application of lifting force to the locking spring resulting in raising movement of the lockingrpin 25'as aforesaid, the lower arm 24 tends to rock bodily about the'corner defined by the top or neck end edge 19a of the slider wing opening 19 and the bottom of recess '22 (see Fig. 2) which it is permitted to do by virtue of the loose seating of the arm and 28 in said recess. it

will also be observed, by analysis of Fig. 2, that as the locking pin end of the spring 23 is raised, the end face of the hook 30 presses downwardly against the bottom of the recess portion 21a, with the result that the free ends of the spring are slightly spread. The combined result of the rocking movement permitted the lower spring arm 24 and the aforesaid spreading of the free ends of both spring arms is to effect a slight stroke of the locking pin end of the spring 23 in upward direction as seen in the drawings. While this stroke is of exceedingly short length, it is nevertheless sufficient to substantially reduce the force required to be applied against the cam surface 29b of the locking spring by the pull tab trunnions to effect raising of the locking pin 25.

It is also to be noted that the spring arms 24, 29 may each flex independently of one another, since neither spring arm is rigidly aflixed to the upper slider wing 10. This ability of each spring arm to flex on its own account renders the spring as a whole more flexible as compared to the locking spring disclosed in my prior application Serial No. 136,689 aforesaid and is another factor in reducing the force required to lift the locking pin to its raised or non-locking position. Thus, by seating and loosely securing the free ends of the spring 23 in oppositely arranged upper-wing recesses according to the present invention, both spring arms are equally flexible and unhampered in their functioning, the force required to lift the locking pin is decreased, a simple and secure seating of the locking spring is achieved, and

at the same time a novel and simplified assembly of the locking spring with slider is made possible.

Such novel assembly is illustrated in part in Fig. 6,

the view showing the slider blank before it is folded, so

that the two wings 10 and 11 and the connecting neck portion 14 extend in a common plane, it being understood that the bail 18 and the recesses 21, 22 have been formed in preliminary operations. The spring 23 has also been preformed to its final contour in another preliminary operation or operations. To assemble the locking spring with the slider blank, it is only necessary to relate the locking spring and slider blank as shown, and to initiate assembly by pushing the spring towards the blank at an angle of approximately. 45 (see arrow A), with the result that the free end portion of the spring clips on to the portion 31 of the blank which extends intermediate the recesses 21 and 22. Thereupon, the locking spring 23 is swung counter-clockwise (see arrow B) so that its upper arm 29 moves through opening 19 in the upper Wing portion of the slider blank and its lower area 24 is received in said opening. During this latter movement, the T-end 28a of the lower spring arm and the hook end 29d, 30 of the upper arm seat within a snap action in the recesses 22, 22a and 21, 21a, respectively, and, in so doing, interlock with the upper wing portion of the blank. Thereupon, the blank may be folded to bring the upper and lower wings to their final parallel relation as indicated in the preceding views.

Thus, the invention provides for assembly of the locking spring 23 in a simple and fast operation, and at the same time achieves a secure spring seating which is thereafter maintained due to the fact that there are no opposing forces tending to move the spring in the opposite (uncoupling) direction with respect to the plane of the upper wing 10.

As many changes could be made in carrying out the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. A locking slider for slide fasteners comprising parallel upper and lower wings having side flanges defining a slider channel and being connected by a neck portion, a bail affixed to and forming with the outer face of the the slider channel, a pull tab having trunnions received in the bail eye whereby the pull tab is pivotally and slidably connected to the bail, a substantially U-shaped locking spring having both its arms formed resilient and being provided adjacent its bend portion with a locking pin normally projecting through said opening into the slider channel, one arm of the locking spring being operative in the bail eye and overlying the pull tab trunnions and having a cam surface adapted to be engaged by the pull tab trunnions when the latter partake of the sliding move- 7 ment thereby to effect flexing of the locking spring in direction as to lift the locking pin from the slider channel, and means on the free ends of both arms of the locking spring loosely yet lockingly interfitting in recesses in the under and outer faces, respectively, of the upper wing, said means and recesses enabling the locking spring to be clipped on to said upper wing and also providing a non-rigid connection between each resilient arm of the locking spring and said upper wing whereby each said arm may flex independently of the other arm of the locking spring.

2. A locking slider for slide fasteners comprising parallel upper and lower wings having side flanges defining a slider channel and being connected by a neck portion, a bail aflixed to and forming with the outer face of the upper wing an elongated eye, the upper wing being provided with an opening disposed between the bail eye and the slider channel, a pull tab having trunnions received in the bail eye whereby the pull tab is pivotally and slidably connected to the bail, a substantially U-shaped locking spring having both its arms formed resilient and being provided adjacent its bend portion with a locking pin normally projecting through said opening into the slider channel, one arm of the locking spring being operative in the bail eye and overlying the pull tab trunnions and having a cam surface adapted to be engaged by the pull tab trunnions when the latter partake of their sliding movement thereby to effect flexing of the locking spring in direction as to lift the locking pin from the slider channel, the other arm of the locking spring being substantially straight and being operatively contained within said opening, and means on the free ends of both arms of the locking spring loosely yet lockingly interfitting in recesses in the under and outer faces, respectively, of the upper wing, said means and recesses enabling the locking spring to be clipped on to said upper wing and also providing a non-rigid connection between each resilient arm of the locking spring and said upper wing whereby each said arm may flex independently of the other arm of the locking spring.

3. A locking slider for slide fasteners comprising parallel upper and lower wings having side flanges defining a slider channel and being connected by a neck portion, a bail afiixed to and forming with the outer face of the upper wing an elongated eye, the upper wing being provided with an opening disposed between the bail eye and the slider channel, a pull tab having trunnions received in the bail eye whereby the pull tab is pivotally and slidably connected to the bail, a substantially U-shaped locking spring having both its armed force resilient and being provided adjacent its bend portion with a locking pin normally projecting through said opening into the slider channel, one arm of the locking spring being operative in the bail eye and overlying the pull tab trunnions and having a cam surface adapted to be engaged by the pull tab trunnions when the latter partake of their sliding movement thereby to effect flexing of the locking spring in direction as to lift the locking pin from the slider channel, said one arm terminating in a hook loosely seating in a recess provided in the outer face of the upper wing, the other arm of the looking spring being substantially straight throughout its full length and being operatively contained within said up- .7 per-wing opening," the free end of said other-arm being loosely engaged in a recess provided-in the under face of the upper wing.

4. A locking slider for slide fasteners comprising parallel upper and lower-wings having side flanges defining a slider channel and being conncctedby a neck portion, a bail afiixed to and forming with the outer face of the upper Wing an elongated eye, the upper wing being provided with an opening disposed between the bail eye and the slider channel, a pull'tab having trunnions received in the bail eye whereby the pull tab is pivotaliy and slidably connected to the bail, a substantially U-shaped locking spring having both its arms formed resilient and being provided adjacent its bend portion with a locking pin normally projecting through said opening into the slider channel, one arm of the locking spring being operative in the bail eye and overlying the puil tab trunnions and having a cam surface adapted to be engaged by the pull tab trunnions when the latter partake of their sliding'movement thereby to effect flexing of the locking spring in direction as to lift the locking pin from the slider channel, said one arm having a substantially straight free-end portion terminating in an angularly disposed hook end, said straight free-end portion and hook end loosely seating in correspondingly shaped recesses provided in the outer face of the upper wing, the other arm of the locking spring being substantially straight and being operative within said upper-wing opening, the free end of said other arm terminating in a transversely extending cross part forming with said free-end portion a T, said cross part and free-end portion of said other spring arm loosely seating in a T-shapcd recess provided in the under face of the upper wing.

5. A locking slider for slide fasteners as set forth in claim 1, wherein said clip-on connection is constructed -8 andarranged so as to'permit spreadingof the arms of the locking spring accompanied by limitedbodily rotational movement of said locking spring in the direction of locking pin lifting movement, but to preclude longitudinal movement of said locking spring.

6. A locking slider for slide fasteners as set forth in claim 3, wherein said recesses are disposed on the longitudinal center line of the slider and extend from the top edge of the upper-Wing opening toward the slider neck partion, whereby the free-end portions of the locking spring arms embrace between them a small length portion of the slider wing disposed intermediate said recesses, the construction and arrangement being such that upon the pull tabtrunnions engaging the cam surface of the upper spring arm the lower arm rocks in locking-pin lifting direction about the corner between the top edge of the opening and the bottom of the under-face recess independently of the flexing of said lower arm, and that the free ends of the spring arms are spread apart a slight amount.

7. A locking slider for slidefasteners as set forth in claim 3, wherein said under face recess is offset from said upper face recess in the direction of the bottom end of the slider.

References tlited in the file of this patent UNiTED STATES PATENTS 2,373,523 Winterhalter Apr. 10, 1945 2,502,055 Marinsky -2 Mar. 28, 1950 2,523,740 Ulrich Sept. 26, 1950 2,535,508 Natzler Dec. 26, 1950 2,551,381 Legat May 1, 1951 2,569,051 Grofi Sept. 25, 1951 2,629,912 Ulrich Mar. 3, 1953 

